In China for the closing ceremony of the Beijing Games, he said he wanted to end the "medals-for-all culture" and bring back the competitive element to school games.

He called for children to be given the chance of taking part in a greater range of school sports – from canoeing and cycling to the martial arts and, controversially, even boxing.

Mr Brown said he wanted to enlist the women stars of the Beijing Games, such as swimmer Rebecca Adlington, runner Christine Ohuruogo and cyclist Victoria Pendleton, to overcome the reluctance of many girls to take up sport.

His call came at the end of a hugely successful Olympics for Great Britain which saw the nation pick up 47 medals, coming fourth in the medals table compared to 36th in the 1996 Atlanta Games.

Its heroes will return home today in a gold-nosed plane to celebrate their success.

A spectacular closing ceremony in Beijing yesterday saw the Olympic flag handed over to London Mayor Boris Johnson, followed by a taste of what the 2012 Games will offer symbolised by a hi-tech red double-decker bus which peeled open to reveal David Beckham.

Mr Brown said Ministers will this week announce "substantial investment" in school sports. The Government is aiming to ensure that all children are doing at least five hours a week of sport or physical exercise by 2012.

Schools will be encouraged to extend competition in their own sports and to link up with local sports clubs in order to broaden the range of events and facilities available.

Mr Brown said he wanted to see an end to the "medals-for-all culture" in schools

"We have started to correct what I believe was the tragic mistake of previous years of reducing the competitive element in schools sports," he said.

Greater participation by children and young people would pay dividends in terms of improving health and reducing obesity while providing a breeding ground for future champions, he added.

Addressing a party in Beijing to mark the handover, he praised the success of Team GB, telling the assembled sports stars they had "captured the imagination of our country".

He said: "Inspired by the success of the Beijing Games and proud of all our athletes, and the young athletes, the next generations who are coming up, we can look forward to 2012 building on Beijing as being the best Olympic Games ever."

Mr Johnson said "sport was coming home".

"The next summer Games return to a country which I frequently boast has either invented or codified just about every major world sport," he said.

"We will draw on that heritage and we will draw on our wit, flair, imagination and ingenuity to build on what we've all witnessed in Beijing and deliver a fantabulous Olympics in what I consider to be not only my home, but the home of sport."

In fact, in typically flamboyant style – he went one better and told the Chinese "ping pong is coming home".

Mr Johnson told the assembled Team GB athletes and officials that Britain invented the game beloved of the Chinese.

Its origins, he told the crowd, lay in the dining rooms of Victorian England.

He said: "I say this respectfully to our Chinese hosts who have excelled so magnificently at ping pong. Ping pong was invented on the dining tables of England in the 19th century and it was called whiff whaff.

"That is the essential difference between us and the rest of the world. Other nations – the French – looked at a dining table and saw an opportunity to have dinner. We looked at a dining table and saw an opportunity to play whiff whaff.

"That is why London is the sporting capital of the world. And I say to the Chinese, and I say to the world: Ping pong is coming home, athletics is coming home, sport is coming home."

But he said he "mourned the passing" of the Ancient Greek pankration event "whose chief exponent was Milo of Croton, whose signature performance involved carrying an ox the length of the stadium, killing it with his bare hands and then eating it on the same day."

He joked he was trying to persuade London Olympic chiefs to bring it back for 2012.

Olympics Minister Tessa Jowell insisted that there could be no back-sliding about the legacy of the 2012 Games, despite concerns about the £9.3bn budget.

She added: "Nobody is prepared to compromise on legacy, because legacy was such a very important part of the commitment we made to London when we bid for the Games."

Mr Brown, who had stood laughing during the Mayor's performance, said: "I thank him on his speech in which he has furthered Chinese-British relations by everything that he has said."

Meanwhile, 40,000 people celebrated the handover in London, joined by the greatest Olympian in history, US swimmer Michael Phelps.